DE102021119528A1 - Bearing arrangement of a swash plate in a steering gear component and surgical instrument - Google Patents

Abstract

The present invention provides a bearing arrangement (40) for a swash plate (14) in a steering gear component (33), the swash plate (14) being arranged such that it can rotate about an axis of rotation (10) in a radial bearing which is located in a receiving opening (330) of the steering gear component (33) is present. The radial bearing is a sliding bearing (35) and the bearing arrangement (40) has at least one axial securing device (36) which is arranged axially adjacent to a first side of the swash plate (14) and engages with the steering gear component (33). Furthermore, a surgical instrument (1) is disclosed that has this bearing arrangement (40) of a swash plate (14) in a steering gear component (33).

Description

The invention relates to a bearing arrangement for a swash plate in a steering gear component and to a surgical instrument which has such a bearing arrangement.

Surgical instruments are known from the prior art which can be guided manually or by a robot and which have tools whose tool tip can be pivoted by means of a plurality of pivoting members which engage in one another. These pivot links are connected to a variety of steering wires or cables to provide fine control of the tool tip. A more even force distribution in all bending directions can be achieved with many thin steering wires compared to a few thicker steering wires.

Out of U.S. 5,454,827 It is known to couple such steering wires to a spatially adjustable disk arranged in an actuating unit on the proximal side, which is connected via a rod to a manually actuatable control lever, so that a movement of the spatially adjustable swash plate results in a corresponding relative movement of the distal-side pivoting members and thus pivoting of the tool tip caused.

The design of the drive for the steering wires with the spatially adjustable swash plate on which the steering wires are mounted has the advantage that this enables a spatially compact design and only one component has to be moved in order to be able to address all steering wires.

US 10,105,128 B2 discloses a surgical instrument with a mechanism to control the movement of a swash plate in two degrees of freedom via link rods with drives on the proximal side, however the swash plate cannot be rotated in the instrument.

It is also known in a surgical instrument to use a steering gear component to transmit drive setting angles to a swash plate for spatial alignment in two degrees of freedom/spatial directions, with the steering gear component being rotationally decoupled from the swash plate by a ball bearing. Cardanic mounting of the swash plate on a main shaft transmits a rotational movement of the instrument shaft to the swash plate, so that the spatial position of the swash plate is determined by superimposing the movements of the steering gear component and the main shaft.

Depending on the structural design, it is not always possible to use a ball bearing.

Based on this state of the art, it is the object of the present invention to provide an alternative to a ball bearing for a swash plate in a steering gear component, which mounts a swash plate in a steering gear component in a rotationally decoupled manner, without the transmission of movement in two degrees of freedom/spatial directions to the swash plate for control of an instrument tool is affected via steering wires.

This object is achieved by a bearing arrangement having the features of claim 1.

The further object of providing a surgical instrument that has a bearing arrangement for the spatially adjustable swash plate that is an alternative to a ball bearing is achieved by the surgical instrument having the features of independent claim 9 .

Further developments and preferred embodiments of the storage arrangement and the surgical instrument are set out in the dependent claims.

According to a first embodiment of the bearing arrangement according to the invention for a swash plate in a steering gear component, the swash plate is arranged in a radial bearing such that it can rotate about an axis of rotation. This is present in a receiving opening of the steering gear component. According to the invention, the radial bearing is a sliding bearing and the bearing arrangement has at least one axial securing device which is arranged axially adjacent to a first side of the swash plate and engages with the steering gear component.

In contrast to a conventionally used ball bearing, which allows rotation as the only degree of freedom, with a plain bearing not only rotation is possible, but also a translational movement in the direction of the axis of rotation, especially with a corresponding force influence on the plain bearing, which, however, is avoided by the arrangement of the axial securing device . According to the invention, this prevents the swash plate from tilting and jamming in the steering gear component, so that the rotation of the swash plate in the steering gear component and thus the function of the bearing arrangement is ensured.

In principle, it is conceivable that two axial securing devices can be used for axial securing on both sides directions are used that secure the swash plate, which is slide-mounted in the steering gear component, from slipping or tilting on both sides.

In a preferred embodiment of the bearing arrangement according to the invention, the swash plate has a radial, i. H. pointing in the radial direction, outer peripheral surface, which is axially adjoined on one side by a circumferentially protruding annular web which has an axial, d. H. pointing in the axial direction, provides contact surface. The receiving opening has a first inner circumferential surface with a first diameter in a first hollow-cylindrical section and a second inner circumferential surface with a second diameter in a second hollow-cylindrical section, which is smaller than the first diameter, so that there is an annular shoulder between the first inner circumferential surface and the second inner circumferential surface , which provides an axial abutment surface for the axial contact surface of the ring land, which is arranged in the first hollow cylindrical section. In this way, the swash plate can be fixed with the ring web on the side facing away from the axial securing device on the ring shoulder in the receiving opening. In this case, the ring web is arranged between the axial securing device and the axial stop surface, which is associated with reduced assembly work.

In a further embodiment of the bearing arrangement according to the invention, it is provided that the plain bearing, which is provided by a low-friction pair of materials, is present on at least one pair of friction surfaces, with a first pair of friction surfaces consisting of the axial contact surface on the annular web of the swash plate and the axial stop surface in the receiving opening of the steering gear component and a second pair of friction surfaces consist of the outer peripheral surface of the swash plate and the second inner peripheral surface of the receiving hole of the steering gear member. If the plain bearing is on the first pair of friction surfaces consisting of an axial ring web contact surface and an axial receiving stop surface, the arrangement of a sliding disk is sufficient. If the plain bearing is present on the second pair of friction surfaces consisting of the outer peripheral surface of the swash plate and the second inner peripheral surface of the receiving opening, a plain bearing bush is used. A plain bearing bush with a corresponding one-sided collar can be used as a plain bearing for both pairs of friction surfaces.

Optionally, the slide bearing can also extend to a pair of friction surfaces, which consists of an outer peripheral surface of the annular ridge and the first inner peripheral surface in the receiving opening of the steering gear component.

To form the slide bearing from the low-friction material pairing, the respective contact surfaces of the friction partners from the friction surface pairing can each have a coating of a material from the material pairing or can consist of a material from the material pairing. One friction partner can also consist of a material from the low-friction material pairing and the other partner can have a coating on the contact surface made of the other material from the low-friction material pairing. Additionally or alternatively, the sliding bearing can have a lubrication. The plain bearing can preferably have a plain bearing bushing which is arranged in the receiving opening and has one of the materials from the low-friction material pairing.

In a further embodiment, the bearing arrangement according to the invention can also provide a plain bearing between the axial securing device and the first side of the swash plate, in that the axial contact surfaces of the axial securing device and the swash plate facing one another also have a low-friction material pairing.

In a further preferred embodiment of the bearing arrangement according to the invention, the axial securing device is provided by a threaded ring with an external thread, with the steering gear component having a corresponding internal thread for engagement with the threaded ring. The screw engagement advantageously makes it possible for a permissible axial play predetermined for the swash plate to be adjustable by screwing in the axial securing device, which is designed as a threaded ring, in the steering gear component.

In a further embodiment, the swash plate of the bearing arrangement according to the invention is arranged on a shaft which defines the axis of rotation. For this purpose, the shaft has a spherical section on which the shaft diameter is widened to form the spherical contour, and the swash plate has a receiving recess on its inside that is at least partially adapted to the spherical section, so that the swash plate can be moved about two axes perpendicular to the axis of rotation without axial offset the shaft is mounted. In order to transmit a rotation or an angle of rotation of the shaft to the swash plate, there are two guide grooves on the spherical section of the shaft in its outer surface, which extend diametrically and in the longitudinal direction of the shaft and into which two pins engage, which extend diametrically and radially inwards pointing at the swashplate and an inner side of the swash plate are arranged.

This advantageously results in a torsionally rigid connection between the shaft and the swash plate, which allows a rotational angle transmission even with a large angular offset (± 40° and more), but is still very compact and easy to manufacture and assemble.

According to yet another embodiment of the bearing arrangement, the receiving recess in the swash plate can be spherical in shape corresponding to the ball section, whereby the receiving recess acts like a joint socket on both sides and the clutch is thus completely fixed axially. A two-part design of the swash plate enables assembly in that the swash plate parts are mounted on the ball section to complete the swash plate.

According to an alternative embodiment, the receiving recess in the swash plate has a spherical section and a cylindrical or widening section, so that the swash plate is only fixed on one side by the spherical section and mounting on the spherical section is made possible by the cylindrical or widening section when pushed onto the shaft in the direction of the ball section.

The surgical instrument according to the invention, which has a bearing arrangement of a swash plate in a steering gear component, provides in a first embodiment that the bearing arrangement is a bearing arrangement according to the invention, since the bearing arrangement according to the invention is particularly suitable for installation in a surgical instrument that has a main shaft and a having a hollow shank coaxial with a longitudinal axis of the main shaft. At the proximal end of the shaft (here the end closer to the actuator) is an actuating unit and at the distal end of the shaft there is a tool tip with a tool that can be actuated via an actuating element that is mounted in the shaft in an axially displaceable manner and that also extends through a longitudinally axial through-bore of the Main shaft extends and is in operative connection with the actuating unit on the proximal side. The bearing arrangement according to the invention is designed for the spatial alignment of the swash plate in relation to the main shaft in cooperation with a drive on the proximal side, so that a movement of the drive on the proximal side causes the tool tip to pivot.

With the steering gear component, the bearing arrangement has an interface with the drive on the proximal side in order to transmit its adjustment angle to the swash plate for controlling the distal tool tip. The spatial orientation of the swash plate in relation to the main shaft by moving the drive on the proximal end causes the tool tip to pivot, which can be pivoted relative to the longitudinal axis of the shaft via a joint mechanism. In one embodiment, the joint mechanism can consist of pivoting members arranged at the distal end of the shaft, which are connected to the proximal-side drive via steering wires running in the longitudinal direction of the shaft, in that the steering wires are mounted on the swash plate, so that a movement of the proximal-side drive results in a corresponding relative movement of the distal-side pivoting members and thus the pivoting of the tool tip.

In a preferred embodiment of the storage arrangement of the surgical instrument according to the invention, the drive on the proximal side can be designed as a motorized drive with at least two drive wheels, e.g. B. driven gears, between which the swash plate is arranged.

In this embodiment, the swash plate is coupled through the bearing arrangement to a third gear which meshes with the two drive wheels, the steering gear component being a steering ring which is non-rotatably coupled to the third gear, preferably being on the axis of rotation of the third gear by 180 ° offset to the third gear wheel, a fourth gear wheel is arranged, which meshes with the two driven gear wheels, so that the toothed chain formed is closed to form a toothed ring, which ensures an evenly circulating force distribution.

Other embodiments, as well as some of the advantages associated with these and other embodiments, will become apparent and better understood from the following detailed description with reference to the accompanying figures. Items or parts thereof that are substantially the same or similar may be given the same reference numbers. The figures are only a schematic representation of an embodiment of the invention.

• 1 eine schematische perspektivische Seitenansicht eines chirurgischen Instruments,
• 2 eine perspektivische Detailansicht einer Taumelscheiben-Lagerungsanordnung aus dem Stand der Technik mit einem Kugellager zur Lagerung der Taumelscheibe in einem Lenkring des Antriebs für das chirurgische Instrument,
• 3 eine Seitenschnittansicht durch eine Lagerungsanordnung nach einer erfindungsgemäßen Ausführungsform,
• 4 eine perspektivische Ansicht auf die Lagerungsanordnung aus 3,
• 5 Detailschnittansicht D der Lagerungsanordnung aus 3 mit angedeuteter Gleitlagerbuchse,
• 6 eine Explosionsansicht der Detailschnittansicht D aus 5 ohne Gleitlagerbuchse,
• 7 eine perspektivische Teilschnittansicht der auf einem Kugelabschnitt einer Hauptwelle angeordneten Taumelscheibe, die zur erfindungsgemäßen Gleitlagerung in einem Lenkring eines Antriebs für ein chirurgisches Instrument ausgebildet ist,
• 8 eine Teilschnittdraufsicht der auf dem Kugelabschnitt der Hauptwelle angeordneten Taumelscheibe aus 7, und
• 9 eine perspektivische Ansicht einer Taumelscheibe zur Gleitlagerung in einem Lenkring eines Antriebs für ein chirurgisches Instrument und zur Anordnung auf einem Kugelabschnitt der Hauptwelle.

show:

• 1 a schematic perspective side view of a surgical instrument,
• 2 a detailed perspective view of a swash plate bearing arrangement the prior art with a ball bearing for mounting the swash plate in a steering ring of the drive for the surgical instrument,
• 3 a side sectional view through a storage arrangement according to an embodiment of the invention,
• 4 a perspective view of the storage arrangement 3 ,
• 5 Detailed sectional view D of the storage arrangement 3 with indicated plain bearing bush,
• 6 an exploded view of detail section view D 5 without plain bearing bush,
• 7 a perspective partial sectional view of the swash plate arranged on a spherical section of a main shaft, which is designed for sliding bearing according to the invention in a steering ring of a drive for a surgical instrument,
• 8th Figure 12 shows a partially sectional plan view of the swash plate arranged on the ball portion of the main shaft 7 , and
• 9 a perspective view of a swash plate for plain bearing in a steering ring of a drive for a surgical instrument and for arrangement on a ball section of the main shaft.

1 shows schematically a surgical instrument 1 with a hollow shank 2, an actuating unit 4 arranged at the proximal end 3 of the shank 2 (shown only schematically) and a tool tip 6 arranged at the distal end 5 of the shank 2 with a tool 7, which has an axially displaceable im Shaft 2 mounted actuating element 8 can be actuated, which is in operative connection with the actuating unit 4 on the proximal side. The actuation unit 4 can be a manually actuable handle or a structural unit designed for robotic use, that is to say it can also be actuated without manual intervention. The tool 7 of the tool tip 6 can, for example, be a tool provided with jaw parts, as in 1 shown, or act to an endoscope, an applicator or the like. The tool tip 6 can be pivoted via a joint mechanism 9 relative to the longitudinal axis 10 of the shank 2, the joint mechanism 9 consisting of pivoting members 11 arranged at the distal end of the shank 5, which are connected via steering wires 12 running in the longitudinal direction of the shank 2 to a proximal end 3 of the shaft 2 arranged drive 13 are connected that a movement of the proximal-side drive 13 causes a corresponding relative movement of the distal-side pivoting members 11 and thus a pivoting of the tool tip 6. Even if only the term steering wires 12 is used above and below, steering cables can also be used functionally, which is why the term steering wires 12 used should also be read and understood synonymously as a steering cable.

The actuating element 8, which is mounted so as to be axially displaceable in the shaft 2, for actuating the tool 7, which consists, for example, of two jaw parts, is designed as a push/pull rod in the illustrated embodiments. In the medical instrument 1 according to the invention, the drive 13 for the steering wires 12 can preferably be designed as a motorized drive 13, which has a spatially adjustable swash plate 14 on which the steering wires 12 are mounted in such a way that a displacement of the Swash plate 14 causes pivoting of the tool tip 6 via the steering wires 12, as z. B. US 10,105,128 B2 or the swashplate bearing arrangement 2 known.

By using a motorized drive 13 for the spatially adjustable disk 14, it is possible to control the steering wires 12 for pivoting the distal-side pivoting members 11 or the instrument tip 6 precisely, sensitively in the smallest of steps and also reproducibly. In addition, the number of steering wires 12 to be used for a motorized drive 13 is irrelevant. The motorized drive 13 can, as in accordance with the prior art 2 known to have two drive units with gears 18 and 19 driven by motors, there bevel gears, between which the swash plate 14 is arranged.

In the surgical instrument 1 according to 1 (combined with 2 - State of the art - or 3 until 11 - bearing arrangement 40 according to the invention), a hollow main shaft 21 is arranged in the shaft 2 and extends coaxially to the longitudinal axis 10 of the shaft 2, which can be rotated about the longitudinal axis 10 of the shaft 2 and extends beyond the proximal end 3 of the shaft 2 into the region of the motorized drive 13 extends. The actuating element 8 for actuating the instrument 7 is mounted in an axially displaceable manner within this hollow main shaft 21 .

The steering wires 12 emerging from the shaft 2 at the proximal end 3 of the shaft 2 are guided at the distal end of the main shaft 21 and can be fanned out via a serrated lock washer (not shown) arranged non-rotatably on the main shaft 21, whereby the radial distance of the steering wires 12 from the Longitudinal axis 10 of the shaft 2 is enlarged. The steering wires 12 running parallel to the longitudinal axis 10 of the shaft 2 behind such a serrated lock washer on the proximal side extend to the swash plate 14 to which the steering wires 12 are fixed. For this purpose, the swash plate 14 has an axially parallel through hole 41 for each steering wire 12, the steering wires 12 being fastened within the through holes 41 via grub screws 41.2 as in FIG 2 or on the proximal side with a clamping disk 41.1, as in 7 and 8th shown, can be fixed and non-positively connected to the swash plate 14 .

The driven gears 18 and 19 are coupled to a third gear 30 which meshes with the two driven gears 18 and 19 and whose axis of rotation B intersects the central axis A of the driven gears 18 and 19 and the longitudinal axis 10 of the shaft 2 . The third gear 30 is also preferably designed as a bevel gear. Due to the three gears 18, 19 and 30 meshing with each other, every movement of the two driven gears 18 and 19 is transmitted directly to the swash plate 14 coupled to the third gear 30, which causes the steering wires 12 to be actuated directly. In order to close the toothed chain formed by the toothed wheels 18, 19 and 30 to form a closed toothed ring, which ensures an even distribution of power, a fourth toothed wheel 31 is arranged on the axis of rotation B of the third toothed wheel 30, offset by 180° with respect to the third toothed wheel 30 is in engagement with the two driven gears 18 and 19, with the fourth gear 31 preferably also being designed as a bevel gear.

The swash plate 14 is in accordance with the known bearing arrangement 2 mounted via a (ball) bearing ring 32 in the steering ring 33 , which is coupled in a rotationally fixed manner to the third gear 30 , in order to enable the swash plate 14 to rotate about the longitudinal axis 10 of the shaft 2 . The steering ring 33, which is coupled in a rotationally fixed manner to the third gear wheel 30, can be rotated freely on a bearing support 331 via a bearing ring 34 in relation to the fourth gear wheel 31, so that rotation of the fourth gear wheel 31 about its axis of rotation B does not cause the steering ring 33 and the swash plate 14 to rotate .

The above in relation to 2 The described embodiments of the drive 13 for the spatial alignment of the swash plate 14 for controlling the tool tip by means of the steering wires 12 also apply to a surgical instrument 1 according to the invention, which has a bearing arrangement 40 according to the invention, as shown in 3 until 5 you can see.

Instead of a ball bearing 32, the bearing arrangement 40 according to the invention has a plain bearing 35 which, unlike a ball bearing, fundamentally not only rotates, but in particular when a force acts on the plain bearing 35, e.g. B. by the distal mechanics, would also allow a translational movement in the direction of the axis of rotation 10 and thus a tilting or wedging of the swash plate 14 in relation to the steering ring 33, which could prevent the rotation of the swash plate 14 in the steering ring 33 and thus impair function . In order to prevent this tilting/wedging and seizing of swash plate 14 when using a plain bearing 35, the bearing arrangement 40 according to the invention provides an axial securing device 36 which, as a counter bearing for plain bearing 35, is arranged axially adjacent to swash plate 14 in receiving recess 330 of steering ring 33 is and with the steering ring 33 is engaged.

The axial securing of the swash plate 14 in the steering ring 33 requires a limitation on both sides, so that it is fundamentally conceivable to axially secure the swash plate 14, which is slide-mounted in the steering ring 33, between two axial securing devices 36 (not shown in the figures). In order to keep the installation effort low, the in 3 until 5 shown embodiment may be preferred, in which the axial securing device 36 fixes the swash plate 14 with an annular web 45 formed on the circumference thereof against a stop surface 33.3 formed in the receiving recess 330, as in particular in the detailed illustration D in 5 and 6 becomes clear.

The swash plate 14, which is also in 7 until 9 can be seen, in the example shown has an outer peripheral surface 45.1 and an annular web 45 which protrudes axially on one side and adjoins it on one side. This provides an axial contact surface 45.2 adjoining the outer peripheral surface 45.1, which faces away from the first side of the swash plate 14 on which the axial securing device 36 is arranged.

The receiving opening 330 in the steering ring 33 is designed with several hollow-cylindrical sections for receiving the swash plate 14, which is particularly good in 6 you can see. In a first hollow-cylindrical section, the receiving opening 330 has a first inner peripheral surface 33.1 with a first diameter and in a second hollow-cylindrical section a second inner peripheral surface 33.2 with a second diameter that is smaller than the first diameter, so that between the first inner peripheral surface 33.1 and the second Inner peripheral surface 33.2 is an annular shoulder, which provides the axial stop surface 33.3 for the axial contact surface 45.2 of the annular ridge 45 in the first hollow-cylindrical section recording finds. As in 5 to see, the annular web 45 of the swash plate 14 is arranged secured between the axial securing device 36 and the axial stop surface 33.3.

There are no restrictions on the design of the slide bearing 35 . The slide bearing 35, which is defined by the contacting surfaces of the friction partners swash plate 14 and steering ring 33, can be provided by selecting a correspondingly low-friction material pairing on the contacting surfaces of the swash plate 14 and the steering ring 33. Suitable material pairings can be, for example, stainless steel Nitronic® 1.3965 - 1.4021 (stainless steel, hardened); Polytetrafluoroethylene - 1.4021 (stainless steel, hardened) or brass (CuZn39Pb3) - brass (CuZn39Pb3), without the scope of protection being limited thereto. That is, the contact surfaces can each have a coating made of a material from the material pairing or the friction partners themselves can each consist of a material from the material pairing. Additionally or alternatively, the sliding bearing 35 can have a lubrication.

The surfaces of the friction partners that are in contact, on which the plain bearing 35 is provided by a low-friction material pairing, have a first pairing of friction surfaces consisting of the axial contact surface 45.2 on the ring web 45 of the swash plate 14 and the axial stop surface 33.3 in the receiving opening 330 of the steering ring 33. A second pair of friction surfaces, on which the plain bearing 35 is present, consists of the outer peripheral surface 45.1 of the swash plate 14 and the second inner peripheral surface 33.2 in the receiving opening 330 of the steering ring 33. The plain bearing 35 can preferably be replaced by a plain bearing bushing, which is 5 is indicated by dashed lines, which is arranged in the receiving recess 330 of the steering ring 33, consists of a material of the low-friction material pairing and the sliding contact surfaces on the axial stop surface 33.3 and the second inner peripheral surface 33.2 for the axial contact surface 45.2 and the outer peripheral surface 45.1 of the swash plate 14 provides. The axial securing device 36 also prevents such a plain bearing bushing 35 from slipping out axially.

Optionally (not shown), the slide bearing (coating, bushing) 35 can extend to a (third) pair of friction surfaces, which consists of an outer peripheral surface 45.3 of the annular web 45 of the swash plate 14 and the first inner peripheral surface 33.1 in the receiving opening 330 of the steering ring 33. Also not shown is the further possible plain bearing between the axial securing device 36 and the first side of the swash plate 14 at the contacting surface sections.

In the example shown in the figures, the axial securing device 36 is designed as a threaded ring 36 with an external thread 36.1, with the steering gear component 33 having a corresponding internal thread 33.4 in the receiving opening 330. With the axial securing device designed as a threaded ring 36 , the permissible play predetermined for the swash plate 14 can be adjusted by the screwing depth of the threaded ring 36 in the steering gear component 33 . The adjustability of the bearing arrangement 40 advantageously enables manufacturing and assembly tolerances to be compensated for in order to ensure the optimal functioning of the slide bearing 35 . Furthermore, the plain bearing surfaces can also be reduced to a minimum in order to further counteract the tilting of the swash plate 14 in the steering ring 33 .

7 until 9 illustrate the mounting of the swash plate 14 on the main shaft 21 of a surgical instrument 1 (cf. 1 ). The spatial alignment of the swash plate 14 for pivoting the tool tip 6 via the steering wires 12 is achieved by superimposing the rotational position of the main shaft 21 and the adjustment angle of the drive on the proximal side (cf. 2 ) causes. The storage arrangement is structurally simple and compact and easy to assemble.

The main shaft 21 has a ball section 24 for the ball-joint mounting of the swash plate 14, on two guide grooves 22 extending in the longitudinal direction of the shaft 21 and introduced into the ball section 24 on both sides or diametrically. The swash plate 14 has a contoured receiving recess 44 that is at least partially adapted to the ball section 24 and from which two diametrically and radially inward-pointing pins 42 extend, which engage in the guide grooves 22 on the ball section 24 of the main shaft 21. To mount the pins 42, the swash plate 14 can have two diametrically radial through holes 43, so that the pins 42 can be inserted from the outside of the swash plate 14 through the through hole 43 until they emerge on the inside of the swash plate 14 and radially to the desired length protrude inward. Alternatively, in embodiments that are not shown, the pins 42 can be fastened to the swash plate 14 in two diametrically radial blind bores running from the inside, or the pins 42 can be cohesively connected to the swash plate 14 on the inside, e.g. B. be made in one piece.

The ball bearing in this way swash plate 14 can from a neutral position in which the swash plate 14 lies in a plane perpendicular to the longitudinal or rotational axis 10, about two spatial axes perpendicular to the rotational axis 10 (A, B, cf. 2 ) can be pivoted. In addition, a rotation angle of the shaft 21 can be transferred to the swash plate 14 by the engagement of the pins 42 in the guide grooves 22 .

The tilting or twisting of the swash plate 14 about one or both axes of rotation A, B relative to the longitudinal axis 10 of the shaft 2 causes, via the steering wires 12, that the instrument tip 6 on the distal side is pivoted in a corresponding manner relative to the longitudinal axis 10 of the shaft 2. By transmitting a rotational movement of the main shaft 21 about the longitudinal axis 10 of the shank 2 to the swash plate 14 , the tool tip 6 coupled to the main shaft 21 on the distal side can be rotated about the longitudinal axis 10 of the shank 2 .

In 8th It can be seen that the receiving recess 44 in the example shown consists of a proximal-side spherical section and a distal-side cylindrical section, which allows the swash plate 14 to be mounted by sliding it on from the proximal-side end of the main shaft 21 . As an alternative to a cylindrical section, a widening section (not shown) can be provided on the distal side. The swash plate 14 is only fixed on one side on the ball section by the spherical section on the proximal side, but is held by the tension of the steering wires 12, which are passed through the passage openings 41 here and are fastened with a clamping ring 41.1 arranged on the proximal side, so that the swash plate 14 is fixed in the axial direction. In a modified embodiment, also not shown, the receiving recess 44 of the swash plate 14 can be formed corresponding to the ball section 24 without a cylindrical or widening section, only with a spherical section, so that the ball-and-socket bearing is completely fixed axially. However, this embodiment requires the swash plate 14 to be designed in at least two parts in order to enable assembly on the ball section 24 .

Reference List

1

medical instrument

2

shaft

3, 5

Proximal, distal end (shaft)

4

operating unit

6, 7

tool tip, tool

8th

actuator

9

joint mechanism

10

longitudinal axis

11

swivel link

12

steering wire

13

drive

14

swashplate

18, 19

gear (driven)

21

main shaft

22

guide groove

23

through hole

24

ball section

27, 29

bearing pin

28

universal joint washer

30, 31

third, fourth gear

32, 34

bearing ring

33, 330, 331

Steering ring, receiving opening, bearing support

33.1, 33.2

first inner peripheral surface, second inner peripheral surface

33.3, 33.4

Axial stop surface, thread

35

Plain bearing (layer/bush)

36, 36.1

Axial locking device/thread ring, thread

40

storage arrangement

41, 41.1, 41.2

Through hole, mounting washer, grub screw

42

Pen

43, 44

locating hole, locating recess

45, 45.1

Ring land, outer peripheral surface of swash plate

45.2, 45.3

axial contact surface, outer peripheral surface ring land

QUOTES INCLUDED IN DESCRIPTION

This list of documents cited by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Patent Literature Cited

• US5454827 [0003]
• US 10105128 B2 [0005, 0032]

Claims (13)

Bearing arrangement (40) of a swash plate (14) in a steering gear component (33), the swash plate (14) being arranged such that it can rotate about an axis of rotation (10) in a radial bearing which is present in a receiving opening (330) of the steering gear component (33), thereby characterized in that the radial bearing is a sliding bearing (35) and the bearing arrangement (40) has at least one axial securing device (36) which is arranged axially adjacent to a first side of the swash plate (14) and engages with the steering gear component (33). Storage arrangement (40) after claim 1 , characterized in that - the swash plate (14) has an outer peripheral surface (45.1) and a peripherally projecting annular web (45) adjoining it axially on one side, which has an annular web (45) facing away from the first side of the swash plate (14) and attached to the outer peripheral surface (45.1) adjacent axial contact surface (45.2), and - the receiving opening (330) has a first inner peripheral surface (33.1) with a first diameter in a first hollow-cylindrical section and a second inner peripheral surface (33.2) with a second, smaller diameter in a second hollow-cylindrical section than the first diameter, so that there is an annular shoulder between the first inner peripheral surface (33.1) and the second inner peripheral surface (33.2), which provides an axial stop surface (33.3) for the axial contact surface (45.2) of the annular ridge (45), which in the first is arranged in a hollow-cylindrical section, the ring web (45) between the axial securing device ( 36) and the axial stop surface (33.3). Storage arrangement (40) after claim 2 , characterized in that the slide bearing (35) is provided by a low-friction pair of materials on at least one pair of friction surfaces, a first pair of friction surfaces consisting of the axial contact surface (45.2) and the axial stop surface (33.3) and a second pair of friction surfaces consisting of the outer peripheral surface (45.1) and the second inner peripheral surface (33.2), the slide bearing (35) optionally extending to a pair of friction surfaces consisting of an outer peripheral surface (45.3) of the ring web (45) and the first inner peripheral surface (33.1). Storage arrangement (40) after claim 3 , characterized in that the plain bearing (35) has a plain bearing bush (35) which is arranged in the receiving opening (330) and has one of the materials from the low-friction material combination. Storage arrangement (40) according to at least one of Claims 1 until 4 , characterized in that the bearing arrangement (40) provides a sliding bearing between the axial securing device (36) and the first side of the swash plate (14). Storage arrangement (40) according to at least one of Claims 1 until 5 , characterized in that the axial securing device (36) is provided by a threaded ring (36) with an external thread (36.1), and the steering gear component (33) has a corresponding internal thread (33.4), with a predetermined permissible play for the swash plate (14). can be adjusted by screwing in the axial securing device (36) in the steering gear component (33). Storage arrangement (40) according to at least one of Claims 1 until 6 , characterized in that the swash plate (14) is arranged on a shaft (21) which defines the axis of rotation (10), the shaft (21) for supporting the swash plate (14) having a spherical section (24), and the The swash plate (14) has a contoured receiving recess (44) which is at least partially adapted to the ball section (24), wherein - the ball section (24) has two diametrically arranged guide grooves (22) extending in the longitudinal direction of the shaft (21) and - on the swash plate (14), two diametrically and radially inward-pointing pins (42) are arranged, each pin (42) engaging in one of the guide grooves (22), so that an angle of rotation of the shaft (21) can be transferred to the swash plate (14). Storage arrangement (40) after claim 7 , characterized in that the receiving recess (44) corresponding to the ball section (24) is spherical, the swash plate (14) being designed in two parts, or the receiving recess (44) has a spherical section (45) and a cylindrical or widening section (46). Surgical instrument (1) with a storage arrangement of a swash plate (14) in a steering gear component (33), characterized in that the storage arrangement is a storage arrangement (40) according to at least one of Claims 1 until 8th is. Surgical instrument (1) after claim 9 , characterized in that the surgical Instrument (1) is designed with a main shaft (21) running coaxially to a hollow shaft (2) and an actuating unit (4) arranged at the proximal end (3) of the shaft (2) and an actuating unit (4) at the distal end (5) of the shaft ( 2) has an arranged tool tip (6) with a tool (7) which can be actuated via an actuating element (8) which is mounted in the shaft (2) in an axially displaceable manner and which extends through a longitudinally axial through bore (23) in the main shaft (21) and is in operative connection with the actuating unit (4) on the proximal side, the tool tip (6) being pivotable via a joint mechanism (9) relative to the longitudinal axis (10) of the shaft (2), and the joint mechanism (9) having a drive (13) on the proximal side is in operative connection, which has the swash plate (14). Surgical instrument (1) after claim 9 or 10 , characterized in that the joint mechanism (9) consists of pivoting members (11) arranged at the distal end (5) of the shaft (2) which are connected to the proximal-side drive (13 ) are connected in that a movement of the proximal-side drive (13) causes a corresponding relative movement of the distal-side pivoting members (11) and thus pivoting of the tool tip (6), the steering wires (12) being mounted on the swash plate (14). Surgical instrument (1) according to at least one of claims 9 until 11 , characterized in that the proximal-side drive (13) is designed as a motorized drive (13) with at least two drive wheels (18, 19), between which the swash plate (14) is arranged. Surgical instrument (1) after claim 12 , characterized in that the swash plate (14) is coupled by the bearing arrangement (4) to a third gear (30) which meshes with the two drive wheels (18, 19), the steering gear component (33) being a steering ring (33 ) which is non-rotatably coupled to the third gear (25), and wherein preferably on the axis of rotation of the third gear (30) offset by 180 ° to the third gear (30) a fourth gear (31) is arranged, which with the two driven gears (18, 19) is engaged.

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